I have received your letter dated 2/3/1394 A.H. May Allah guide you and grant you success! It included three questions about Wahhabism. Following is my answer:

Q 1: You asked about Wahhabism and whether it is a fifth Madh-hab (School of Jurisprudence) or follows one of the four Madh-habs.

A: The term Wahhabism is used by many people to refer to the call initiated by Imam Muhammad ibn ‘Abdul-Wahhab ibn Sulayman Al-Tamimy Al-Hanbaly (may Allah be merciful to him). He is called along with his followers ‘Wahhabis’. Every knowledgeable person must have heard about Shaykh Muhammad ibn ‘Abdul-Wahhab’s movement (may Allah be merciful to him). He called for pure Tawhid (belief in the Oneness of Allah) and warned people against all forms of Shirk (associating others with Allah in His Divinity or worship), such as supplicating to the dead, trees, rocks or the like. He (may Allah be merciful to him) followed in creedal matters the Madh-hab (School of Jurisprudence) of the Salaf (righteous predecessors) while in subsidiary matters he followed the Madh-hab of Imam Ahmad ibn Hanbal Al-Shaibany (may Allah be merciful to him). This is clear in the books and Fatwas (legal opinions) of Muhammad ibn ‘Abdul-Wahhab and in the books of his followers and offspring which are published. Imam Muhammad ibn ‘Abdul-Wahhab appeared at a time when Islam was alienated, the Arabian Peninsula and other areas were engulfed in ignorance and worshiping idols was widespread. So the Shaykh took it upon himself to strive and struggle, and devoted himself to destroying all means of misguidance.

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He employed all the possible ways leading to the spread of Tawhid free from any kind of superstition. Allah, out of His Bounty, made Imam Muhammad ibn Sa‘ud, Prince of Al-Dir‘iyyah at that time, accept the call. Thus, the Prince, his sons, those under his authority and his followers supported the Imam, may Allah reward them, forgive them and grant their offspring success to all that pleases Him and to what sets right the affairs of His Servants! All regions of the Arabian Peninsula have lived under this righteous call to the present day. Thus, Imam Ibn ‘Abdul-Wahhab’s call was in accordance with the Qur’an and Sunnah (whatever is reported from the Prophet). Wahhabism is not a fifth Madh-hab as some ignorant and prejudiced people claim; rather, it is a call to the ‘Aqidah (creed) of Salafiyyah (those following the way of the righteous predecessors) and a way of reviving the main aspects of Islam and Tawhid which was forgotten in the Arabian Peninsula.